K65.9
Billable codePeritonitis, unspecified
The ICD-10 code for peritonitis, unspecified is K65.9.
Clinical notes
Also known as
Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.
- Bacterial peritonitis NOS
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •This code describes an unspecified presentation. If the medical record documents a more specific detail (e.g. laterality, type, or affected site), a more specific sibling code should be used instead — see Related codes below.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 5679
Associated MS-DRGs
K65.9 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.
- DRG 314Other Circulatory System Diagnoses with MCC
- DRG 315Other Circulatory System Diagnoses with CC
- DRG 316Other Circulatory System Diagnoses without CC/MCC
- DRG 371Major Gastrointestinal Disorders and Peritoneal Infections with MCC
- DRG 372Major Gastrointestinal Disorders and Peritoneal Infections with CC
- DRG 373Major Gastrointestinal Disorders and Peritoneal Infections without CC/MCC